Zika Virus Logo

Zika Virus


Zika is a disease caused by Zika virus. It is spread to people primarily through the bite of an infected mosquito. The illness is usually mild with symptoms lasting for several days to a week. There is no vaccine or treatment for Zika.

Zika Virus Overview

Transmission of Zika

Zika virus is known to spread to people through mosquito bites via mosquitoes of the Aedes species. These are the same mosquitoes that spread dengue and chikungunya viruses. About 1 in 5 people infected with Zika virus become ill.

Zika can be transmitted sexually from a person who has Zika to their partner. This can happen even if the person with Zika does not show symptoms. It is unclear how long the virus persists in fluids of those infected. For couples in their child-bearing years, the latest guidelines for prevention of sexual transmission of Zika virus should be followed.

Pregnant women at risk of Zika should consult their obstetrician and make sure they are familiar with the latest guidance from the CDC. This is particularly important if there has been recent travel to countries affected by Zika virus.

Zika infection during pregnancy can cause serious birth defects, including microcephaly and other problems in infants including eye defects, hearing loss and impaired growth. The CDC suggests that pregnant women in any trimester should consider postponing travel to regions where the Zika virus is active. Women trying to get pregnant should consult with their doctor or health provider before travel to those regions.

Symptoms of Zika

Illness resulting from Zika infection is typically mild, with symptoms lasting for several days to a week.

Symptoms of Zika include:

  • Fever
  • Rash
  • Joint pain
  • Muscle pain
  • Headache
  • Conjunctivitis (red eyes)

According to the CDC, symptoms typically begin 2 to 7 days after being bitten by an infected mosquito. Because the symptoms of Zika are mild, it is difficult for people to recognize that they may be infected; as such, it is important to pay attention to whether any mosquito bites were sustained 2 to 7 days prior to the appearance of symptoms.

The CDC further indicates that the need for hospitalization is uncommon, while deaths resulting from Zika are quite rare.

Prevention of Zika Transmission

Whether a person is infected or not, the best way to prevent the spread of Zika is to avoid getting mosquito bites. If you or someone you know plans on traveling to countries where Zika virus or other viruses spread by mosquitoes (such as dengue or chikungunya) are found, take the following steps:

  • Use insect repellents

When used as directed, insect repellents are safe and effective for everyone, including pregnant and nursing women. Most insect repellents can be used on children in proper concentrations.  Do not use products containing oil of lemon eucalyptus in children under the age of three years.

Repellents containing DEET, picaridin, IR3535, and some oil of lemon eucalyptus and para-menthane-diol products provide long lasting protection. If you use both sunscreen and insect repellent, apply the sunscreen first and then the repellent.

Do not spray insect repellent on the skin under your clothing. Always follow the label instructions when using insect repellent or sunscreen.

  • Treat clothing with permethrin or purchase permethrin-treated clothing.
  • When weather permits, wear long-sleeved shirts and long pants.
  • Use air conditioning or window/door screens to keep mosquitoes out of your home, hotel room or place of work. Remember that the mosquitoes are believed to transmit Zika virus bite during the daytime as well as early morning and evening.
  • Help reduce the number of mosquitoes inside and outside your home or hotel room by emptying standing water from containers such as flowerpots or buckets.


Currently no vaccine exists to prevent Zika virus disease. Follow these guidelines to treat symptoms:

  • Get plenty of rest
  • Drink fluids
  • Take fever- and pain-relieving medicine. Do NOT take Aspirin or NSAIDs (such as ibuprofen.


CDC has issued a travel alert (Level 2-Practice Enhanced Precautions) for people traveling to regions and certain countries where Zika virus transmission is ongoing.

Follow the latest CDC guidance regarding areas affected with Zika by clicking here.

The virus is spreading rapidly so the list of countries affected may not reflect the current distribution due to the inherent lag in diagnostic testing and reporting.